A kind of Ru-Ni-Mo oxide@foam metal self-supporting material and its preparation and application as HER catalytic material

Abstract

The present application relates to the field of materials, in particular to a kind of Ru-Ni-Mo oxide@foam metal self-supporting material with villiform, including foam metal, fiber villiform molybdenum oxide grown on its skeleton, and nano ruthenium and nano nickel metal particles dispersed in molybdenum oxide.The present application also includes the preparation and application of the material.The material described in the present application has excellent HER performance.

Description

Technical Field

[0001] This invention relates to the field of catalytic materials, specifically to HER catalytic materials. Background Technology

[0002] With the continuous depletion of fossil fuels such as oil, coal, and natural gas, and the increasing prominence of environmental problems, exploring and developing new energy technologies has become an urgent priority to address energy shortages. Hydrogen energy is a renewable and clean energy source with many outstanding advantages, including wide availability, renewability, high calorific value, and zero pollution, making it the optimal choice to replace traditional fossil fuels. Aluminum-water fuel cells are safe, efficient, and low-cost primary environmentally friendly batteries that combine the storage and release of electrical and hydrogen energy. One of the keys to improving the performance of aluminum-water fuel cells is the development of hydrogen evolution cathode materials with good electrocatalytic activity and stability. Platinum, a precious metal, exhibits the best intrinsic catalytic activity for hydrogen evolution reaction (HER); however, its low reserves, high cost, and instability significantly hinder its large-scale industrial application. Therefore, finding efficient, low-cost, and durable non-platinum-based electrocatalysts is essential. Summary of the Invention

[0003] To address the issue of unsatisfactory performance of existing Mo-based HER materials, the primary objective of this invention is to provide a villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material (also referred to as a catalyst in this invention), aiming to provide a novel catalyst with excellent HER catalytic performance.

[0004] The second objective of this invention is to provide a method for preparing the aforementioned villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material and its application as a HER catalyst.

[0005] A third objective of this invention is to provide a battery or device comprising the aforementioned villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material.

[0006] A villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material includes foam metal, fibrous villous molybdenum oxide grown on its skeleton, and nano-ruthenium and nano-nickel metal particles dispersed in the molybdenum oxide.

[0007] This invention provides a novel material based on a foamed metal substrate, with a fibrous, villous active material formed on the substrate's framework. The active material comprises molybdenum oxide and dispersed nano-nickel and ruthenium metal particles. This invention has found that the combination of this unique phase and the fibrous, villous structure achieves a synergistic effect, improving the catalytic performance of HER, particularly its catalytic stability under high current.

[0008] In this invention, the combination of the catalyst's phase composition and its fibrous, villous structure is key to synergistically improving its HER performance.

[0009] In this invention, there are no particular requirements regarding the metal or thickness of the foamed metal. For example, the foamed metal may be at least one of nickel foam, cobalt foam, iron foam, and copper foam. As one embodiment, the thickness of the foamed metal is 1.0–3.0 mm, and the porosity can be 20–99%.

[0010] In this invention, the molybdenum oxide is MoO3 or MoO2. 3-x At least one of MoO2;

[0011] Preferably, in the active material of the ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, the mass ratio of ruthenium-nickel-molybdenum elements is 0.05-0.2:0.4-0.7:1;

[0012] Preferably, in the ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, the content of foam metal is 50-80 wt.%.

[0013] This invention also provides a method for preparing the aforementioned villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, comprising the following steps:

[0014] Step (1):

[0015] Nickel molybdate@foam metal was prepared by reacting a solution containing a nickel source, a molybdate source, a structure directing agent, and foam metal in an open reaction vessel (at atmospheric pressure) at a temperature below 100°C.

[0016] Step (2):

[0017] A ruthenium-nickel molybdate@foam metal precursor was prepared by combining nickel molybdate@foam metal precursor and ruthenium source liquid phase;

[0018] Step (3):

[0019] The villous ruthenium-nickel-molybdate@foam metal precursor was calcined under a reducing atmosphere to obtain the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material.

[0020] In this invention, the key and challenging aspect of material preparation lies in constructing the specific ruthenium-nickel-molybdenum oxide phase and its fibrous villous structure. However, the inventors unexpectedly discovered that the one-step introduction of Ru at low temperatures affects the formation of the fibrous villous morphology, hindering the preparation of the material with the desired morphology and phase. To address the difficulty in preparing the product phase and fibrous villous phase due to the one-step introduction of Ru, this invention has found that pre-reacting the nickel source, molybdate source, and structure-directing agent at low temperatures, followed by treatment with the Ru source, and further combined with subsequent calcination in a reducing atmosphere, unexpectedly achieves synergy. This solves the problem of the difficulty in preparing the fibrous villous phase due to Ru introduction. Furthermore, it also yields a phase in which Ru-Ni nanoparticles are dispersed within the molybdenum oxide. This invention provides a material with the specific phase and morphology, exhibiting excellent HER performance, particularly excellent HER performance under high current.

[0021] In this invention, nickel molybdate@foam metal can be synthesized from a nickel source, a molybdate source, and a structure-directing agent at atmospheric pressure and a temperature below 100°C.

[0022] In this invention, in step (1), the nickel source is Ni. 2+ The water-soluble salt is preferably at least one of nickel nitrate, nickel chloride, and nickel sulfate;

[0023] Preferably, the molybdate source is at least one of sodium molybdate or ammonium molybdate;

[0024] Preferably, the structure-directing agent is at least one of urea and ammonium fluoride;

[0025] Preferably, the molar ratio of Ni in the nickel source, Mo in the molybdate source, and the structure modifier is 0.5–1.5:1:1.5–2.5; more preferably, it is 0.7–1.1:1:1.5–2.

[0026] Preferably, in step (1), the concentration of molybdate source in the initial reaction solution is 0.01–0.1 mol / L;

[0027] Preferably, the weight ratio of foam metal to molybdate source is 1:0.1 to 0.5;

[0028] Preferably, the temperature of the reaction in step (1) is ≥80℃ and <100℃; more preferably, it is 80~95℃.

[0029] Preferably, the reaction time in step (1) is 6 to 24 hours, and more preferably 7 to 15 hours.

[0030] In this invention, nickel molybdate@foam metal is innovatively synthesized in advance at low temperature, and then compounded with Ru. This helps to unexpectedly solve the problem that the fibrous fluff structure caused by Ru is prone to collapse, making it difficult to prepare the special phase material.

[0031] In this invention, the ruthenium source includes at least one of ruthenium trichloride, ruthenium acetate, and ruthenium acetylacetone;

[0032] Preferably, in step (2), the concentration of the ruthenium source in the liquid-phase composite starting solution is 0.01–0.1 M. In this invention, controlling the concentration of the ruthenium source during the liquid-phase composite stage helps to further synergistically improve the HER performance of the prepared material.

[0033] In this invention, in step (2), the molar ratio of Ru in the ruthenium source to Mo in the molybdate source is greater than or equal to 0.05:1, further greater than or equal to 0.1:1, and considering the treatment effect and cost, it is further preferred to be 0.1 to 1:1, and even more preferably 0.2 to 0.5:1.

[0034] Preferably, in step (2), the temperature of the treatment stage is 10-60°C, more preferably 20-60°C, and even more preferably 35-45°C. At the preferred treatment temperature, better synergistic effects can be obtained, which can further improve the HER performance of the treated material.

[0035] Preferably, in step (2), the processing time is 1 to 12 hours, and more preferably 3 to 10 hours.

[0036] In this invention, in step (3), the reducing atmosphere is a hydrogen-containing atmosphere, preferably, the hydrogen content is 3-10V%, more preferably 4-6V%.

[0037] Preferably, the calcination and heat preservation temperature is 300–600°C, more preferably 400–500°C;

[0038] Preferably, the roasting and heat preservation time is 0.5 to 4 hours, and more preferably 1 to 2 hours.

[0039] The present invention also provides an application of the aforementioned villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as a HER catalyst.

[0040] The present invention has found that the material with the special fiber villous morphology and phase can exhibit excellent HER performance and can be used as a HER catalyst.

[0041] Preferred applications of this invention include its use as a HER catalyst for hydrogen production via water electrolysis and / or for the preparation of battery electrode materials.

[0042] The present invention also includes a battery electrode, which is the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material described in the present invention.

[0043] Preferably, the battery is a fuel cell, such as a lithium fuel cell or an aluminum-water fuel cell.

[0044] The present invention also provides a battery that uses the aforementioned fluffy ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as an electrode.

[0045] The present invention has the following beneficial effects:

[0046] (1) This invention provides a novel catalyst that, based on the combination of the aforementioned special phase and fibrous villous structure, achieves synergistic effects, improving the catalytic performance of HER, particularly its catalytic stability under high current. For example, at a current density of 1000 mA·cm⁻¹... -2 At this point, its cathode overpotential is only 135mV, enabling hydrogen evolution under high current.

[0047] (2) In this invention, the nickel source, molybdate source, and structure directing agent are reacted at low temperature before being treated with Ru, and further combined with subsequent calcination in a reducing atmosphere. This unexpectedly achieves synergy, solving the problem of Ru-induced difficulties in preparing fibrous villous phases. Moreover, it also yields a phase in which Ru-Ni nano-metal particles are dispersed in molybdenum oxide. In this invention, the preparation method described above can obtain materials with the special phase and morphology, which exhibit excellent HER performance, especially excellent HER performance under high current.

[0048] This invention employs direct in-situ growth of catalysts on a foamed metal substrate, eliminating the need for binders. The catalyst material is tightly bonded to the conductive substrate, greatly improving catalytic stability.

[0049] (3) The preparation process of this invention is simple to operate, the reaction conditions are mild, the performance is excellent, and it has the potential for large-scale industrial production and application. Attached Figure Description

[0050] Figure 1 SEM image of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared in Example 1;

[0051] Figure 2 TEM image of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared in Example 1;

[0052] Figure 3 The image shows the XRD pattern of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared in Example 1.

[0053] Figure 4 SEM image of the catalyst prepared in Comparative Example 4;

[0054] Figure 5 LSV curves of the catalysts prepared in Example 1 and Comparative Examples 1-4 in Application Example 1;

[0055] Figure 6 The villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared in Example 1 was tested at 100 mA·cm⁻¹. -2 Voltage versus time curve under constant current;

[0056] Figure 7 The constant current discharge curve of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared in Example 1 in Application Example 2;

[0057] Figure 8 The LSV curves are for Examples 2 to 6. Detailed Implementation

[0058] To more clearly illustrate the objectives, technical solutions, and advantages of this invention, the present invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely for explaining the invention and should not be construed as limiting its scope. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the protection scope of this invention.

[0059] If the manufacturers of the reagents or instruments used are not specified, they are all conventional products that can be purchased commercially.

[0060] The villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material of the present invention includes the following steps:

[0061] Step (1): The foam metal was ultrasonically cleaned in alcohol solution and acid solution, and nickel salt, molybdate and structure directing agent were added to prepare an aqueous solution. The foam metal was immersed in the prepared solution to carry out a water bath reaction (at normal pressure and temperature below 100℃) to obtain the nickel foam precursor. After washing and drying, nickel molybdate@foam metal was obtained.

[0062] Step (2): The nickel molybdate@foam metal is immersed in a ruthenium salt solution for reaction, rinsed clean and dried to obtain the ruthenium-nickel molybdate@foam metal precursor;

[0063] Step (3): The precursor is subjected to thermal reduction treatment to obtain the HER catalyst.

[0064] The alcohol solution mentioned in step (1) can be ethanol, acetone, or isopropanol, and the acid solution can be hydrochloric acid or sulfuric acid. The concentration of the acid solution is 1–3 mol / L, and the ultrasonic cleaning time is 20–30 min. The ultrasonic cleaning time in step (1) is 0–15 min.

[0065] In a specific embodiment of the present invention, the water bath reaction in step (1) is carried out under normal pressure, and the temperature can be 80-100℃, or even 80-95℃, and the reaction time can be 6-24h.

[0066] In a specific embodiment of the present invention, in step (1), the molar ratio of Ni in the nickel source, Mo in the molybdate source, and the structure modifier is 0.5-1.5:1:1.5-2.5; more preferably 0.7-1.1:1:1.5-2.

[0067] In one specific embodiment of the present invention, the concentration of the ruthenium salt solution in step (2) is 0.01–0.1 mol / L. The nickel molybdate@foam metal is just submerged in the ruthenium source solution. "Just submerged" means that the solution level is higher than the nickel molybdate@foam metal, and the height difference between the solution level and the nickel molybdate@foam metal is >0 cm ≤ 0.5 cm. The molar ratio of Ru in the ruthenium source to Mo in the molybdate source is greater than or equal to 0.05:1, further greater than or equal to 0.1:1, more preferably 0.1–1:1, and even more preferably 0.2–0.5:1.

[0068] In one specific embodiment of the present invention, the impregnation reaction temperature in step (2) is 10-60°C, more preferably 20-60°C, and even more preferably 30-45°C, and the reaction time is 1-12h, preferably 4-10h.

[0069] In one specific embodiment of the present invention, the thermal reduction treatment temperature in step (3) is 300-600℃ and the time is 0.5-4h; the thermal reduction treatment atmosphere is H2 / Ar and the hydrogen volume concentration is 3-10%.

[0070] The foamed metal described in this invention can be a foamed metal material known in the industry. For example, in the following case, the porosity of the foamed nickel is 20-99%, and more specifically 80-98%.

[0071] Example 1

[0072] (1) Cut out a piece of nickel foam (porosity 95%) with a diameter of 1cm*3cm*1.5mm and place it in ethanol for ultrasonic degreasing for 15min. Then place it in a hydrochloric acid solution with a molar concentration of 2mol / L and ultrasonicate for 20min to remove the surface oxides. Then rinse it with deionized water and let it air dry for later use.

[0073] (2) Weigh 1.4 mmol nickel chloride hexahydrate, 0.2 mmol ammonium molybdate tetrahydrate and 2.5 mmol urea and stir thoroughly to dissolve in 15 ml deionized water. Add the foamed nickel prepared in (1) and react at 90℃ (marked as T) under normal pressure for 8 h. Take it out and rinse it with deionized water. Place it in a 60℃ oven to dry to obtain nickel molybdate@foamed nickel.

[0074] (3) The nickel molybdate@foam nickel obtained in (2) was just immersed in 10 ml of 0.05 mol / L ruthenium trichloride aqueous solution and placed in an oven at 40 ℃ for 4 h. After rinsing with deionized water and drying, the ruthenium-nickel molybdate@foam nickel precursor was obtained.

[0075] (4) The ruthenium-nickel-molybdate@nickel foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 400°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 1 hour, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@nickel foam HER catalyst.

[0076] The microstructure of the prepared catalyst was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The SEM results are as follows: Figure 1 As shown, the TEM image is as follows Figure 2 As shown in the figure, a fibrous, fluffy material is uniformly grown on the surface of the nickel foam. XRD analysis of the material yielded the following results: Figure 3 It can be seen that it contains MoO3 oxide, and nano-Ru and Ni metal particles are dispersed within it.

[0077] Comparative Example 1

[0078] Compared with Example 1, the only difference is that steps (3) and (4) are omitted, and the material obtained in step 2 is used directly as the HER catalyst.

[0079] Comparative Example 2

[0080] Compared with Example 1, the only difference is that step (4) is not performed, and the material obtained in step (3) is used as the HER catalyst.

[0081] Comparative Example 3

[0082] Compared with Example 1, the only difference is that step (3) is omitted, and the material from step 2 is directly processed in step 4 to obtain the HER catalyst.

[0083] Comparative Example 4

[0084] Compared with Example 1, the only difference is that step (3) is not performed, and the Ru originally used in step 3 is added to the raw material mixing stage in step (2) (that is, an equal amount of Ru is added to the solution system before the reaction in step 2). Other operations are the same as in Example 1.

[0085] SEM images of the prepared material are shown below. Figure 4 It is evident that the one-pot reaction of Ru with nickel and molybdate makes it difficult to prepare materials with a fibrous, fluffy morphology.

[0086] Application Example 1

[0087] At room temperature, a three-electrode system was used, with the self-supported HER material finally prepared in each case as the working electrode, a carbon rod as the counter electrode, a Hg / HgO electrode as the reference electrode, and a 4 mol / L KOH solution as the electrolyte. Electrochemical performance was tested using a Gamry electrochemical workstation.

[0088] (1) Catalytic activity test

[0089] First, CV activation was performed using a CV test program. The test voltage range was 0.2 to -0.4 vs. RHE, the scan rate was 50 mV / s, and the cycle time was 50 times to allow the electrode to reach a stable state. After activation, the program was switched to LSV program, with a test voltage range of 0.2 to -0.7 vs. RHE and a scan rate of 2 mV / s. The LSV curve was corrected for iR. The overpotentials at different currents were measured as follows: Figure 5 As shown, the self-supported ruthenium-nickel-molybdenum oxide@nickel foam catalyst obtained in Example 1 can be seen at 100 mA·cm⁻¹ -2 and 1000mA·cm -2 The overpotentials at current densities were only 47 mV and 135 mV, respectively, and the electrocatalytic activity was significantly better than that of other comparative examples. This shows that the presence of ruthenium and the thermal reduction process both play an important role in improving the catalyst activity.

[0090] (2) Stability test

[0091] After CV activation, switch the program to a timing potentiometer (CP) program, setting the current to 100mA and the time to 172800s. For example... Figure 6 As shown, at 100mA·cm -2 After continuous hydrogen production at a current density for 48 hours, the overpotential of the catalyst did not change significantly, demonstrating that the HER catalyst has good stability during alkaline water electrolysis.

[0092] Application Example 2

[0093] At room temperature, using an aluminum metal plate as the anode and 4MKOH solution as the electrolyte, the self-supported ruthenium-nickel-molybdenum oxide@foam nickel catalyst prepared in Example 1 was used as the hydrogen evolution cathode. The area of ​​the counter electrode was strictly controlled, and the device was designed and assembled into an aluminum-water fuel cell.

[0094] The discharge performance of an aluminum-water fuel cell was tested using the Wuhan Landian Battery Testing System. Figure 7 For a current density of 50 mA·cm -2 The discharge curve obtained after continuous discharge for 2 hours at a given current density. Based on... Figure 7 As can be seen, the aluminum-water fuel cell prepared by the self-supported ruthenium-nickel-molybdenum oxide@foamed nickel catalyst provided in Example 1 of the present invention exhibits a high discharge voltage (0.56V) while simultaneously undergoing hydrogen evolution under high current, and achieves a discharge capacity density of 2665 mAh·g. -1 It is close to the theoretical capacity of metallic aluminum, 2980 mAh·g. -1 The energy density also reached 1487.7 Wh·kg. -1 Meanwhile, it maintains relatively stable discharge performance, indicating that the binder-free electrode material structure of the present invention has good hydrogen evolution discharge activity and stability, and the energy utilization rate of aluminum metal is high.

[0095] Example 2

[0096] This embodiment provides a fluffy ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, which differs from Example 1 only in the impregnation temperature and time in step 3, and is prepared according to the following steps:

[0097] (1) Cut out a piece of nickel foam (porosity 95%) with a diameter of 1cm*3cm*1.5mm and place it in isopropanol for ultrasonic degreasing for 15min. Then place it in a sulfuric acid solution with a molar concentration of 2mol / L and ultrasonic for 20min to remove the surface oxides. Then rinse it with deionized water and air dry it for later use.

[0098] (2) Weigh 1.4 mmol nickel chloride hexahydrate, 0.2 mmol ammonium molybdate tetrahydrate and 2.5 mmol urea and stir thoroughly to dissolve in 15 ml deionized water. Add the foamed nickel prepared in (1) and react at 90 °C under normal pressure for 8 h. Take it out and rinse it with deionized water. Place it in a 60 °C oven to dry and obtain nickel molybdate@foamed nickel.

[0099] (3) The nickel molybdate@foam nickel obtained in (2) was just immersed in 10 ml of 0.05 mol / L ruthenium trichloride aqueous solution and immersed at room temperature of 25°C for 8 h. After rinsing with deionized water and drying, the ruthenium-nickel molybdate@foam nickel precursor was obtained.

[0100] (4) The ruthenium-nickel-molybdate@nickel foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 400°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 1 hour, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@nickel foam HER catalyst.

[0101] Example 3

[0102] This embodiment provides a fluffy ruthenium-nickel-molybdenum oxide@foam metal self-supporting material. Compared with Example 1, the only differences are the size of the nickel foam and the amounts and concentrations of nickel salt, molybdate, urea, and ruthenium salt. It is prepared according to the following steps:

[0103] (1) Cut out 3cm*6cm*1.5mm foam nickel (porosity 95%), put it in ethanol and sonicate to remove oil for 15min, then put it in hydrochloric acid solution with a molar concentration of 2mol / L and sonicate for 20min to remove surface oxides, then rinse it with deionized water and air dry it for later use.

[0104] (2) Weigh 5 mmol nickel chloride hexahydrate, 1 mmol ammonium molybdate tetrahydrate and 13.3 mmol urea and stir thoroughly to dissolve in 80 ml deionized water. Add the foamed nickel prepared in (1) and react at 90 °C under normal pressure for 10 h. Take it out and rinse it with deionized water. Place it in a 60 °C oven to dry and obtain nickel molybdate@foamed nickel.

[0105] (3) Cut the nickel molybdate@foam nickel obtained in (2) into pieces of 1cm*3cm*1.5mm size, and immerse them in 10ml of 0.07mol / L ruthenium trichloride aqueous solution. Place them in an oven at 40℃ for immersion for 4h, take them out, rinse them with deionized water, and dry them to obtain the ruthenium-nickel molybdate@foam nickel precursor.

[0106] (4) The ruthenium-nickel-molybdate@nickel foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 400°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 1 hour, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@nickel foam HER catalyst.

[0107] Example 4

[0108] This embodiment provides a villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, which differs from Example 1 only in the amount of nickel salt, and is prepared according to the following steps:

[0109] (1) Cut out a piece of nickel foam (porosity 95%) with a diameter of 1cm*3cm*1.5mm and place it in ethanol for ultrasonic degreasing for 15min. Then place it in a hydrochloric acid solution with a molar concentration of 2mol / L and ultrasonicate for 20min to remove the surface oxides. Then rinse it with deionized water and let it air dry for later use.

[0110] (2) Weigh 1.0 mmol nickel chloride hexahydrate, 0.2 mmol ammonium molybdate tetrahydrate and 2.5 mmol urea and stir thoroughly to dissolve in 15 ml deionized water. Add the foamed nickel prepared in (1) and react at 90 °C under normal pressure for 8 h. Take it out and rinse it with deionized water. Place it in a 60 °C oven to dry and obtain nickel molybdate@foamed nickel.

[0111] (3) The nickel molybdate@nickel foam precursor obtained in (2) was just immersed in 10 ml of 0.05 mol / L ruthenium trichloride aqueous solution, placed in an oven at 40 ℃ for 4 h, taken out and rinsed with deionized water, and dried to obtain ruthenium-nickel molybdate@nickel foam precursor.

[0112] (4) The ruthenium-nickel-molybdate@nickel foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 400°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 1 hour, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@nickel foam HER catalyst.

[0113] Example 5

[0114] This embodiment provides a fluffy ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, which differs from Example 1 only in the thermal reduction treatment temperature and holding time, and is prepared according to the following steps:

[0115] (1) Cut out a piece of nickel foam (porosity 95%) with a diameter of 1cm*3cm*1.5mm and place it in ethanol for ultrasonic degreasing for 15min. Then place it in a hydrochloric acid solution with a molar concentration of 2mol / L and ultrasonicate for 20min to remove the surface oxides. Then rinse it with deionized water and let it air dry for later use.

[0116] (2) Weigh 1.4 mmol nickel chloride hexahydrate, 0.2 mmol ammonium molybdate tetrahydrate and 2.5 mmol urea and stir thoroughly to dissolve in 15 ml deionized water. Add the foamed nickel prepared in (1) and react at 90 °C under normal pressure for 8 h. Take it out and rinse it with deionized water. Place it in a 60 °C oven to dry and obtain nickel molybdate@foamed nickel.

[0117] (3) The nickel molybdate@foam nickel obtained in (2) was just immersed in 10 ml of 0.05 mol / L ruthenium trichloride aqueous solution, placed in an oven at 40 ℃ for 4 h, taken out and rinsed with deionized water, and dried to obtain ruthenium-nickel molybdate@foam nickel precursor.

[0118] (4) The ruthenium-nickel-molybdate@nickel foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 500°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 2 hours, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@nickel foam HER catalyst.

[0119] Example 6

[0120] This embodiment provides a villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material. Compared with Example 1, the difference is that the foam nickel metal substrate is replaced with a foam copper metal substrate, and the water bath temperature and time are changed. It is prepared according to the following steps:

[0121] (1) Cut out a 1cm*3cm*1.5mm piece of copper foam (porosity 95%) and put it into ethanol for ultrasonic degreasing for 15min. Then put it into a 2mol / L hydrochloric acid solution for ultrasonic degreasing for 20min to remove surface oxides. Then rinse it with deionized water and air dry it for later use.

[0122] (2) Weigh 1.4 mmol nickel chloride hexahydrate, 0.2 mmol ammonium molybdate tetrahydrate and 2.5 mmol urea and stir thoroughly to dissolve in 15 ml deionized water. Add the foamed copper prepared in (1) and react at 95°C under normal pressure for 7 h. Take it out and rinse it with deionized water. Then immerse it in a 60°C oven to dry it to obtain nickel molybdate@foamed copper.

[0123] (3) The nickel molybdate@copper foam obtained in (2) was placed in 10 ml of ruthenium trichloride aqueous solution with a concentration of 0.05 mol / L, and immersed in an oven at 40°C for 4 h. After rinsing with deionized water and drying, the ruthenium-nickel molybdate@copper foam precursor was obtained.

[0124] (4) The ruthenium-nickel molybdate@copper foam precursor obtained in (3) was placed in a horizontal tube furnace and heated to 400°C at a heating rate of 5°C under a 5% H2 / Ar atmosphere. After holding at the temperature for 1 hour, it was cooled to room temperature to obtain the self-supporting ruthenium-nickel-molybdenum oxide@copper foam HER catalyst.

[0125] Examples 2-6 were tested using the method described in Example 1, and the results are shown below. Figure 8 The results show that the materials prepared in each case are similar to those in Example 1, and also exhibit beneficial HER properties.

[0126] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, characterized in that, It includes foam metal, fibrous molybdenum oxide grown on its framework, and nano-ruthenium and nano-nickel metal particles dispersed in the molybdenum oxide; The molybdenum oxide is MoO 3-x ; In the aforementioned ruthenium-nickel-molybdenum oxide@foam metal self-supporting material, the content of foam metal is 50~80 wt.%. The preparation steps of the aforementioned villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material include: Step (1): A solution containing a nickel source, a molybdate source, a structure directing agent, and a foam metal is reacted at a temperature below 100°C and at normal pressure to obtain nickel molybdate@foam metal; the structure directing agent is at least one of urea and ammonium fluoride; the molar ratio of Ni in the nickel source, Mo in the molybdate source, and the structure modifier is 0.5~1.5:1:1.5~2.

5. Step (2): A ruthenium-nickel molybdate@foam metal precursor was prepared by liquid-phase composite of nickel molybdate@foam metal precursor and ruthenium source; the molar ratio of Ru in the ruthenium source to Mo in the molybdate source was 0.1~1:

1. Step (3): The villous ruthenium-nickel-molybdate@foam metal precursor was calcined under a reducing atmosphere to obtain the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material. The firing and heat preservation temperature is 300~600℃.

2. The villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 1, characterized in that, The foam metal is at least one of foam nickel, foam cobalt, foam iron, and foam copper.

3. The villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 1, characterized in that, The thickness of the foamed metal is 1.0~3.0 mm, and the porosity is 20~99%.

4. A method for preparing a villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material according to any one of claims 1 to 3, characterized in that the step include: Step (1): A solution containing a nickel source, a molybdate source, a structure directing agent, and a foam metal is reacted at a temperature below 100°C and at normal pressure to obtain nickel molybdate@foam metal; the structure directing agent is at least one of urea and ammonium fluoride; the molar ratio of Ni in the nickel source, Mo in the molybdate source, and the structure modifier is 0.5~1.5:1:1.5~2.

5. Step (2): A ruthenium-nickel molybdate@foam metal precursor was prepared by liquid-phase composite of nickel molybdate@foam metal precursor and ruthenium source; the molar ratio of Ru in the ruthenium source to Mo in the molybdate source was 0.1~1:

1. Step (3): The villous ruthenium-nickel-molybdate@foam metal precursor was calcined under a reducing atmosphere to obtain the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material. The firing and heat preservation temperature is 300~600℃.

5. The preparation method of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 4, characterized in that, In step (1), the nickel source is Ni. 2+ Water-soluble salts; The molybdate source is at least one of sodium molybdate or ammonium molybdate.

6. The preparation method of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 4, characterized in that, The molar ratio of Ni in the nickel source, Mo in the molybdate source, and the structure modifier is 0.7~1.1:1:1.5~2; In step (1), the concentration of molybdate source in the initial reaction solution is 0.01~0.1 mol / L; The weight ratio of foam metal to molybdate source is 1:0.1~0.

5.

7. The preparation method of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 4, characterized in that, The reaction temperature in step (1) is 80~95℃; The reaction time for step (1) is 6 to 24 hours.

8. The method for preparing the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 4, characterized in that, In step (2), the ruthenium source includes at least one of ruthenium trichloride, ruthenium acetate, and ruthenium acetylacetonate; The molar ratio of Ru in the ruthenium source to Mo in the molybdate source is 0.2~0.5:1; The temperature during the processing stage is 10~60℃; The processing time is 1 to 12 hours.

9. The preparation method of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 4, characterized in that, In step (3), the reducing atmosphere is a hydrogen-containing atmosphere.

10. The method for preparing the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in claim 9, characterized in that, The hydrogen content is 3-10% (V%). The firing and heat preservation temperature is 400~500℃; The roasting and heat preservation time is 0.5~4 hours.

11. The application of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material according to any one of claims 1 to 3 or the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared by any one of claims 4 to 10, characterized in that, It was used as a HER catalyst.

12. The application as described in claim 11, characterized in that, It can be used as a HER catalyst for hydrogen production via water electrolysis and / or for the preparation of battery electrode materials.

13. A battery electrode, characterized in that, The villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in any one of claims 1 to 3, or the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared by any one of claims 4 to 10.

14. The battery electrode as described in claim 13, characterized in that, The battery in question is a fuel cell.

15. A battery, characterized in that, The electrode is made of the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material as described in any one of claims 1 to 3 or the villous ruthenium-nickel-molybdenum oxide@foam metal self-supporting material prepared by any one of claims 4 to 10.

Images